1. Field of the Invention
The invention relates to door structures, and particularly to apparatus for unlocking, opening, closing and locking plug doors of railway house cars.
2. The Prior Art
The prior art includes railway car plug doors of the type in which the front end of the door track curves from an outwardly spaced portion parallel to the car side toward the car side near the front edge of the door opening, with the front portion of the door directly mounted on a track-mounted carriage and the rear portion of the door mounted by means of a crank on a track-mounted carriage for movement into and out of the door opening by direct manual rotation of the crank mounting shaft and manual sliding of the door along the car side between open and closed positions. The prior art also includes car door structures in which longitudinal racks are mounted on the car side and manually actuated pinion driven gear boxes are mounted on the racks and connected to the door for moving it longitudinally of the car side.